Building construction and operations can have extensive direct and indirect impacts on the environment, society, and economy, which are commonly referred to as the 3 P’s (‘People’, ‘Planet’, ‘Pocketbook’). The field of sustainable design seeks to balance the needs of these areas by using an integrated approach to create win-win-win design solutions.

The main objectives of sustainable design are to reduce, or completely avoid, depletion of critical resources like energy, water, and raw materials; prevent environmental degradation caused by facilities and infrastructure throughout their life cycle; and create built environments that are livable, comfortable, safe, and productive.

Buildings use resources (energy, water, raw materials, and etc.), generate waste (occupant, construction and demolition), and emit potentially harmful atmospheric emissions. Building owners, designers, and builders face a unique challenge to meet demands for new and renovated facilities that are accessible, secure, healthy, and productive while minimizing any negative impacts on society, the environment, and the economy. Ideally, building designs should result in net-positive benefits to all three areas.

In addition to including sustainable design concepts in new construction, sustainable design advocates commonly encourage retrofitting existing buildings rather than building anew. Retrofitting an existing building can often be more cost-effective than building a new facility. Designing major renovations and retrofits for existing buildings to include sustainable design attributes reduces operation costs and environmental impacts, and can increase building resiliency. The embodied energy of the existing building, a term expressing the cost of resources in both human labor and materials consumed during the building’s construction and use, are squandered when the building is allowed to decay or be demolished.

While the definition of sustainable building design is constantly changing, seven fundamental principles persist.

Optimize Site Potential

Optimize Energy Use

Protect and Conserve Water

Embodied Energy

Optimize Building Space and Material Use

Enhance Indoor Environmental Quality

Optimize Operational and Maintenance Practices

The issues related to sustainability are so all-encompassing that many feel that a different word should be used. The word “green” is often used because its connotations are flexible and it symbolizes nature, which truly is sustainable. For the same reason, many use the word “ecological.” Still others prefer the phrase “environmentally responsible.” The words might be different, but the goals are the same.

In “The Next Industrial Revolution” (Atlantic Monthly, Oct. 1998), archi- tect William McDonough and scientist Michael Braungart suggest that sustain- ability is based on the following three principles:

• Waste equals food – Everything must be produced in such a manner that, when its useful life is over, it becomes a healthy source of raw materials to produce new things.

• Respect diversity – Designs for every- thing will respect the regional, cul- tural, and materials of a place.• Use solar energy – All energy sources must be nonpolluting and renew- able, and buildings must be solar

responsive.

Many parts of the world are using water faster than it is replenished. The greater the population, the greater the impact on the environment. The more affluent a society, the greater the impact on the environment. For example, a family that lives in a 2500 ft2 (225 m2) house affects the environment far more than a family that lives in a 1000 ft2 (90 m2) house. Thus, it should be noted that for a given impact on the environment, the greater the population, the lower its affluence must be.

Technology has a great impact on the environment. A person today will have a much greater impact on the environment than did a person a couple of centuries ago, when there were no automobiles, air travel, air- conditioning, electrical appliances, electrical lighting, etc. So far, most technology has had a negative impact on the environment. We can change that situation, by using technology that is more benign. We must be recognize that sustainability cannot be achieved only by good technology; it requires us to change our values so that a high quality of life is not equated with high consumption.

Heating, cooling, and lighting are all accomplished by moving energy into or out of a building. Energy use is the most urgent to address, as modern society is critically reliant upon it.